I have tried on both these boots, they both feel comfortable in the shop after trying on varying sizes etc. I really like the BOA system and they version on the Maysis really holds the heel in place but the Ion is also a very nice boot and speed lacing system is fast and works well also.
Both are the same price (note overpriced in New Zealand)

I would like some opinions from others to help with my decision, help sway me one way

I have Rome Libertines at the moment and they are far too flimsy and parky for my riding and I hate laces!